The Taliban takeover is an embarrassment to the Afghan government and its foreign backers, and shows how vulnerable the government remains despite the presence of some 47,000 U.S. and NATO troops.
Meanwhile, a member of the U.S.-led military coalition was killed during a clash with insurgents in western Afghanistan Friday, the coalition said.
Coalition forces engaged militants in a gunbattle in the Shindand district of Herat province and called in an airstrike, a coalition statement said. It did not give any details about how the unidentified service member was killed, or the soldier's nationality.
The U.S. Department of Defense has reported 316 U.S. military deaths in and around Afghanistan, including 199 killed in action, as of April 21.
The Taliban launched their takeover attack Thursday evening on the Giro district of Ghazni province, setting fire to several buildings and cutting communication lines, said provincial deputy governor Kazim Allayer.
The district mayor and four policemen, including the police chief, were killed in a battle with the militants that lasted several hours, Allayer said. Police reinforcements have been sent to the area, Ghazni's deputy police chief Mohammad Zaman said.
Giro is about 110 miles southwest of Kabul.
"Giro collapsed last night, captured by the Taliban after heavy fighting between the police and the Taliban," said Gen. Murad Ali, deputy regional corps commander of the Afghan army.
Ali said that early Friday the Afghan army sent troops from Ghazni and Paktika to assist.
NATO and the U.S.-led coalition said they were aware of the incident.
"The details are very sketchy right now. We're tracking it closely," said Maj. William Mitchell, a spokesman for the coalition.
After a winter lull in attacks, the Taliban have stepped up bombings and attacks in recent weeks, as NATO-led forces push forward with their biggest ever offensive in southern Afghanistan to root out militants in the opium-producing heartland of Helmand province.
Meanwhile in eastern Khost province, gunmen assassinated a criminal investigation policeman as he was driving Friday in Tani district, said provincial police chief Gen. Mohammad Ayub.
A relative in the car was also killed, and the driver was wounded, Ayub said, adding that two suspects have been arrested. It was not immediately clear if it was a personal conflict or an insurgency attack.
In southern Uruzgan, Taliban militants ambushed a police convoy patrolling late Wednesday night, and the ensuing clash left four policemen and six Taliban dead, said provincial police chief Gen. Abdul Qasim Khan.